Continental

Problemi valanghivi

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  Storm Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alta quota
  • Limite del bosco
  • Sotto il limite del bosco

  Probabilità

  Possible

  Dimensione

  1–2

  A storm slab has slowly been building this week and will be the primary driver of instability at middle and upper elevations today. This new snow has fallen on weak, faceted snow which will make it more reactive and take longer to bond to the underlying snow. Take note of how much snow has fallen in the areas you travel, in areas where more than 10” exists expect the hazard to be higher. 

  Hand shears and small test slopes are useful tools for assessing how well the new snow is bonding to older layers. Shooting cracks, recent avalanche activity, and collapsing would all be signs that storm snow instability is increasing. Keep in mind these clues are useful for the upper snowpack, but they will not help you identify persistent weak layers buried deeper in the snowpack (see Problem 2).

  Wet Loose

  If the sun comes out this afternoon, expect a spike in natural wet loose activity on solar aspects particularly on south and west faces as the new dry snow warms up and falls apart. Below 1000ft in areas that did not freeze overnight and received rain rather than snow, wet loose will be possible on all aspects.

  

• 

  Persistent Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alta quota
  • Limite del bosco
  • Sotto il limite del bosco

  Probabilità

  Possible

  Dimensione

  1.5–3

  Weak faceted snow makes up the majority of our snowpack right now, creating multiple layers of concern. There is not one consistent set up you are going to find across our region and each slope should be assessed on an individual basis and should be treated with some skepticism. Pole probing can help you to feel for weak snow below harder layers, but in general it is not advised to try and outmaneuver this problem. Choosing simpler less consequential terrain is the best way to mitigate the hazard.

  New snow and warming temperatures are likely putting some stress on this weak snow. As spring progresses and changes to the snowpack continue to occur, this problem is likely to become more active.

  

• 

  Deep Persistent Slabs

  N

  NE

  E

  SE

  S

  SW

  W

  NW

  • Alta quota
  • Limite del bosco
  • Sotto il limite del bosco

  Probabilità

  Unlikely

  Dimensione

  2–3

  Weak snow near the ground is increasingly common as you move North through our forecast zones, with the Continental zone being the most concerning. Although it still remains unlikely to trigger this layer, areas that have been scoured from strong northeast winds now have a shallower snowpack, making this layer closer to the surface and potentially easier for a rider to trigger.

  This is a low-likelihood but high-consequence problem most likely to be triggered in steep, rocky terrain and areas where the snowpack is thin or scoured. Triggering this layer directly is unlikely at this time, but avalanches that start in the upper snowpack could step down to the basal weak layer.  There is a high degree of uncertainty regarding the poor structure at the base of the snowpack.